RequestRateAndReviewAppAsync is broken

### Describe the bug

When I call RequestRateAndReviewAppAsync a native crash occurs.

### Why is this important?

APIs should work without crashing. Without this APIs users can not be asked to leave a review for an app.

### Steps to reproduce the bug

Install latest WinAppSDK and create an empty C# app.

```csharp
var context = StoreContext.GetDefault();
var hwnd = WinRT.Interop.WindowNative.GetWindowHandle(((App)App.Current).MainWindow);
WinRT.Interop.InitializeWithWindow.Initialize(context, hwnd);
var result = await context.RequestRateAndReviewAppAsync();
```

### Actual behavior

Exception thrown at 0x00007FFB3BEF6104 (Windows.ApplicationModel.Store.dll) in Project-Quick-Open.exe: 0xC0000005: Access violation reading location 0x0000000000000000.

I believe there are no public symbols for this dll, so more details are difficult to provide.

### Expected behavior

If an error occurs that error should be returned. No fatal Access violation.

### Screenshots

_No response_

### NuGet package version

WinUI 3 - Windows App SDK 1.7.3: 1.7.250606001

### Windows version

Windows 11 (24H2): Build 26100

### Additional context

_No response_

Start by reproducing the C# example with Windows App SDK 1.7.3 on Windows 11 24H2, focusing on StoreContext.GetDefault and RequestRateAndReviewAppAsync after window initialization. Investigate the native access violation and verify that failures return an error rather than crashing.

Written by the indexing model from the issue text.